1. Field of the Invention
The present invention relates to a light unit, and more particularly to an intellectual vehicle light unit which compensates the light difference of the environmental light and saves electric energy.
2. Description of Related Art
A light unit used on a bicycle is designed to protect the rider from being hit by vehicles because of low visibility, especially in dark area. The conventional light unit generally is powered by batteries which provide limited power to the light unit and most of the batteries contain material that is harmful to the environment. In order to replace the batteries, green energy is developed such as solar energy or wind energy. However, these green energies require expensive cost and huge equipment, and the natural energy is not stable.
A conventional light unit known to applicant is automatically activated when the environment is dark, and is stopped when the environment has sufficient light. The light unit uses at least one Light Emitting Diode (LED) cooperated with a driving circuit to activate the LED to flash. The LED is electrically connected between the output end of the circuit and a CDS which is connected to a contact point of a spring switch. The spring switch is connected with a resistance and is grounded. The CDS detects the environment light and the spring switch is activated by the vibration of the bicycle.
However, the so called environment light that is detected by the CDS actually is the combination of the environment light and the light from the light unit itself. Therefore, the light unit cannot provide precise light to compensate the difference between the real environment light and the expected illumination feature. Besides, more electric energy is required.
The present invention has arisen to mitigate and/or obviate the disadvantages of the conventional light unit.